This invention relates to medical instruments in general, and more particularly to an improved electronic stethosope which includes superior noise rejection and automatic power shut-off.
Both electronic and accoustic stethoscopes and combinations of these two are well known in the art. A typical example of an electronic stethoscope is that described in U.S. Pat. 3,247,324. A pickup head is accoustically cooupled, by means of a flexible conduit, to a microphone. Signals picked up by the microphone are amplified and provided to a speaker which is accoustically coupled to a conventional binaural headpiece by means of flexible conduits. The particular stethoscope disclosed also permits a direct accoustical connection.
Two basic problems with electronic stethoscopes have been the fact that they do not adequately bring up the low frequencies when filtering out high frequency noises from an external sources such as fluorescent lights and the like and that they are often inadvertently left on causing the battery to drain down and require early replacement.
It is the object of the present invention to provide an improved electronic stethoscope which does not suffer from these disadvantages.